Safety & Code

Entrapment Protection

Definition

Entrapment protection is the UL 325-required set of safety devices on a powered garage door operator that prevents people from being trapped or struck by a closing door. Every residential operator must have at least one primary and one secondary entrapment protection device, typically an auto-reverse contact test and a photo-eye sensor pair.

Entrapment protection is the term used in UL 325 for the combination of safety devices that stop or reverse a powered garage door if a person is in its path. UL 325 is the Underwriters Laboratories standard that applies to all residential and commercial garage door operators sold in the United States. Without compliant entrapment protection, an operator cannot be listed under UL 325 and cannot legally be sold.

The standard requires two types of protection working together.

Primary entrapment protection:

This is the contact reversal system built into the opener itself. When the door meets resistance while closing, the motor reverses. The UL 325 test for this is the 2x4 board test: a flat 1.5-inch tall board placed on the floor must trigger reversal before the door exerts more than 20 pounds of force. The opener's force setting controls the sensitivity of this system.

Secondary entrapment protection:

This is typically a photo-eye sensor pair mounted 4-6 inches above the floor on each side of the door. An infrared beam connects the two sensors. If the beam is broken by a person or object while the door is closing, the door reverses immediately, before contact. On commercial doors, a sensing edge pressure strip on the bottom bar can substitute for photo eyes.

Both types are required because neither alone is sufficient. A photo eye can fail due to dirt, misalignment, or a bright sun angle directly in the beam. The contact reversal catches what the photo eye misses.

For example, a residential opener installed in Colorado after 1993 must have both systems working. A technician who detects a failed photo eye during a tune-up must fix it. An opener with one failed safety device does not meet UL 325 entrapment protection requirements.